1. Technical Field
This invention relates to an electrical contactor and an electrical connecting apparatus that are, for example, applicable as an electrical contactor to contact an electrode provided in a wiring substrate, a semiconductor integrated circuit, etc., and an electrical connecting apparatus including a plurality of electrical contactors.
2. Description of Related Art
A well-known electrical contactor is to electrically connect electrical circuits on wiring substrates arranged to face each other, for example. An example of such an electrical contactor can be found in Patent Document 1 (Japanese Patent Laid-Open No. 2015-40734).
FIG. 23A is an enlarged front sectional view showing a part of a conventional electrical connecting apparatus where a conventional electrical contactor 90 is attached. FIG. 23B is an enlarged side sectional view showing the part where the electrical contactor 90 of FIG. 23A is attached.
FIGS. 23A and 23B show a state where the electrical contactor 90 is provided in a housing 17 of the electrical connecting apparatus and the electrical contactor 90 is electrically connected to an electrode 13 of a device under test and a contact pad 22 of a wiring substrate 15.
For example, the electrical contactor 90 includes two first plungers 91, a second plunger 92, and a compressed coil spring 93. Each of the two first plungers 91 is a plate-like plunger to contact the electrode 13 of a device under test. The second plunger 92 is a plate-like plunger to contact the contact pad 22 provided on the upper surface of the wiring substrate 15.
Each of the first plungers 91 is inserted into the compressed coil spring 93. The second plunger 92 is inserted into the compressed coil spring 93 from a direction opposite to a direction in which each of the first plungers 91 is inserted into the compressed coil spring 93.
The two first plungers 91 are arranged to overlap each other while the second plunger 92 is caught between the first plungers 91. Specifically, while the second plunger 92 is caught between the two first plungers 91, apart where the two first plungers 91 and the second plunger 92 overlap each other is inserted into the compressed coil spring 93. A spring receiving portion 911 of each of the first plungers 91 and a spring receiving portion 921 of the second plunger 92 contact the compressed coil spring 93.
When the electrical connecting apparatus is used while the electrical contactor 90 is incorporated in the housing 17 of the electrical connecting apparatus, the compressed coil spring 93 receives external force to exert elastic force in a vertical direction. This electrically connects a tip portion 91A of each of the first plungers 91 to the electrode 13, while electrically connecting an end portion of the second plunger 92 to the contact pad 22.